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Rev Limit- How high can you go?

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Old 08-27-2012, 07:27 AM
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Necro thread alert, lol.
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Old 08-27-2012, 10:34 AM
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Originally Posted by BARMY
My '04 MX5 SE (aka Mazdaspeed Miata) now spends a lot of time on the track, I've been killing brakes and tyres, so I'm going to go with the 201rwhp map instead of the 233rwhp one and aim to become a better cornerer. The ECU presently stops the action at 6500rpm, which seemed a good thing with the high power map, but was a bit intrusive in several places on the tracks I drive at. So when I finally work out how to play around with the Haltech, can I go with a higher rev limit with less boost?
You can go a higher rev limit with the same amount of boost = more awesome.

I spin my Mazdaspeed to 7600.


Also: Toasting in a 7 year old thread!!!
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Old 08-27-2012, 07:45 PM
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Originally Posted by concealer404
Also: Toasting in a 7 year old thread!!!
Jeez! I obviously hadn't noticed. Sorry 'bout that and thanks for the answer. I'll wind it up to 7250.
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Old 08-27-2012, 09:45 PM
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7600rpm is outside of my comfort zone for a factory motor. The rods aren't going to like that for long. 7250 is a much safer number.
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Old 09-25-2012, 11:07 AM
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Again, sorry for the necro. But reading more about these motors makes me feel happier leaving mine at 6750 bearing in mind it hits 16psi at those revs - because apparently revs kill rods?
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Old 09-25-2012, 11:22 AM
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torque/pressure kills rods.
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Old 09-25-2012, 11:26 AM
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So what rpm can I safely go to?
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Old 09-25-2012, 11:32 AM
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Originally Posted by BARMY
So what rpm can I safely go to?
What is done to your motor? The stock redline of 7200 should be more then safe.
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Old 09-25-2012, 03:14 PM
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Stock redline is 7000. 7200 is safe forever (i.e. endurance cars). 7400 for HPDE/normal track cars. 7600 for street cars that might see that figure once a day for a moment.

Run an HPDE car at 7600 and it will blow up eventually. Run an endurance car at 7600 and it will blow up fast.
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Old 09-25-2012, 07:28 PM
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Originally Posted by Savington
Stock redline is 7000. 7200 is safe forever (i.e. endurance cars). 7400 for HPDE/normal track cars. 7600 for street cars that might see that figure once a day for a moment.

Run an HPDE car at 7600 and it will blow up eventually. Run an endurance car at 7600 and it will blow up fast.
What breaks? Eventually I'd like to get a Supermiata crank gear and wheel, Skunk t-body, and then rev higher...but that's a lot of scratch.
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Old 09-25-2012, 08:30 PM
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idk about you **** but I rev my car to 12k all day every day because the sounds of det make my **** swell
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Old 09-25-2012, 08:32 PM
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Originally Posted by hustler
What breaks? Eventually I'd like to get a Supermiata crank gear and wheel, Skunk t-body, and then rev higher...but that's a lot of scratch.
I think it depends on which head you have and what is done to the head.
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Old 09-25-2012, 09:24 PM
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Originally Posted by shuiend
I think it depends on which head you have and what is done to the head.
The head on my turbo car has supertech springs so that's nice.
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Old 09-25-2012, 10:19 PM
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Originally Posted by hustler
What breaks? Eventually I'd like to get a Supermiata crank gear and wheel, Skunk t-body, and then rev higher...but that's a lot of scratch.
Different stuff breaks depending on the application. Enduro/track cars will typically break the throttle shaft first, then break the crank pulley bolts, then damage the valvetrain (7500+), then stretch the stock rods (7600+). If you expect OEM reliability at 7500+, you need to address all of that.
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Old 09-26-2012, 03:05 AM
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Originally Posted by shuiend
What is done to your motor? The stock redline of 7200 should be more then safe.
Breathing, fueling and a piggy back ECU. No changes to the internals, which I guess is why the previous owner left the redline at 6500 as set at the factory. It's at 16psi at 6500. The 173.4kW = 232hp.
Attached Thumbnails Rev Limit- How high can you go?-blacksters-se-dyno.jpg  
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Old 09-26-2012, 12:28 PM
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Originally Posted by Savington
Different stuff breaks depending on the application. Enduro/track cars will typically break the throttle shaft first, then break the crank pulley bolts, then damage the valvetrain (7500+), then stretch the stock rods (7600+). If you expect OEM reliability at 7500+, you need to address all of that.
I will continue rolling with a spare throttle-body in the track trailer...one day that Skunk TB will join me in holy mantrimony.
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Old 08-22-2014, 12:05 PM
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Originally Posted by ecugrad
I have been pondering rev limits for my squirted N/A 1.6. AFAIK, the stock limit is 7,300 rpm.

Im thinking around 7,800 rpm. My car is tracked and autocrossed EXTENSIVELY in CSP with 13" Wheels. This translates into a bunch of time spent on or near the limiter for autox.

Lets not pretend all motors are equal. So here is what i have on my 1.6L.

Started off completely stock driven by grandma until 46K miles. Then i got it. drove it on the track for a little over 1K miles then. Full exhaust, Intake, Megasquirt 126WHP. Raised the RMP to 7,500 and have been driving it for the past Year and 1/2 for at least 2 track weekends a month. I bounce of the rev limiter almost religiously and beet the hell out of it. I change the oil very 2-3 events stock oil filter and Rotella T6. I have a coolant reroute 180 thermostat and ducting for rad. I never see temps over 185 on the track even when it is 100 gotta love Texas. I have no idea what my oil temps are and that has been on my mind so i'm installing a sensor as soon as i stop being lazy. I run 225 Nt01's 87oct and im waiting for the motor to fail so i can try a hot 1.8.

Last edited by t2couger; 08-22-2014 at 12:25 PM.
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Old 08-22-2014, 12:44 PM
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Wonder if he'll log in for the first time in 4 years to see your reply.
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Old 08-22-2014, 01:53 PM
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Originally Posted by concealer404
Wonder if he'll log in for the first time in 4 years to see your reply.
lol how the hell did i bring this thread back form the dead?
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Old 03-31-2017, 10:30 PM
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Not that I am into necro or anything but this thread is on point. I have done some reading on bumping up the rev limit and this helped me out.

I autocross very competitively quite often (20-30 events/year) and attend 1-3 HPDE's/year. I am looking to increase my rev limit because when I autocross I am too often at the limiter and I end up losing ground/time. Switching to 3rd and then rev matching down is fun but that also loses me time. I am planning on bumping up my limit to 7,500 this season (lower for track days). I think I should be safe. What do you guys think?

Here are my specs:
95 bottom w/ 99 factory head. ~5k miles since it was built.
MS2
210 - 240 whp
Forged rods and ARP hardware all around
FM lightened flywheel
4.1 diff (switching to a 3.9 this season)
225/50-15 tires

According to the FM gearing calculator, with the new rev limit and the 3.9 diff, I can take 2nd to 72 mph!! I can smell a few more FTD's this season.

Thanks in advance.
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